Apparatus for producing nitrogen



June 24, 1930. w. B. VABII ARSDEL 1,765,781

APPARATUS FOR PRODUCING NITROGEN Filed Nov. 10, 1921 s Sheets-Sheet 1 INVEN TOR WALL/967i 5. VA/V fizeszm.

ATTYS.

June 24, 1930. w. B. VAN ARSDEL 1,765,781

APPARATUS FOR PRODUCING NITROGEN Filed Nov. 10, l92l- 3 Sheets-Sheet 2 INVENTOR WALLACE 5. MQ/V/QESDEL 11]! L inn F June 24, 1930. w. BLVAN ARSDEL APPARATUS FOR PRODUCING NITROGEN s Sheet-Sheet 3 INVE'NTOR MLLACE Z3. 'ldq/vflama AT TYS.

Patented June 2 1939 f 1 WALLAcE B. vA ArtsnEnor BERLIN, New HAMPSHIRE, ASSIGNOR 'ro. BROWN coMrANY, or BE IN,- NEW HAMPSHIRE, A CORPORATION or MAINE ArrANArUs roe PRODUCING 'NrrnoenN Application'filed November 10, 1921.. Serial 1V0. 514,191.

This invention relates to apparatus for the production of nitrogen by the combustion of hydrogen inair and the removal of the prodv ucts of combustion fromthe residual gas.

More particularly this invention is c'on-' .cerned with means for supplying a constant ,and regulable amountofair andhydrogen to a, combustionfurnace an'd safety devices forminimizing the danger of explosions or. n ofproducing a gas Wl'llChfiltllGI forms anexplofsive mixture with air or containsjan excess of'airl These and other featuresofthe' in vent-ion will appear froma;morecomplete description of an illustrative embodiment ls-thereof disclosed in-the accompanying drawv ings in Which' I 4 Figure 1 is a diagrammatic View of the apparatus. i a v Figure 2 is a sideelevation partly in section of the furnace, n l A H Figure is an end view thereof.

Figure 4 is a partial plan of the gasometers.

, Figure 5 isa front elevation thereof;

Figures 6 and '7 are front and side detail elevations of the gasometers andmotor regulatingdevices, I

I The flow of a gas inpr'actice is always regulated by making useof. a'drop in pressure across some sort of resistance, an increase in flow being accomplished by either lowering the resistance while keeping the pressure dif- V ference constant or increasingv the pressure diiference while the resistance is; held cons'tant, or by combinations of the two methods. y In the present instanceas the airand hydrogen are mixed-in theicombustion furnace the outlet pressures of 'the gases-are equal, though variable dependenton the use to be.

, madeofithe ga ,.-..Asf it1is quite abnormal that the ratio of the hydrogen tothe air shall be I kept constant so as to permit complete combustion without undue, excess ofjeither hydrogen orflair in; the" finalproduct, it is .essential thatthe initial pressures and the resistances be closely regulated. 'As the finalpressure may vary somewhat, as before stat ed, ittherefore becomes important that the initial pressure; shall be somewhat highand "the; resistances large to causefthe drop in pressure to be considerable in order sures be held closely constant;

slight variations in the final pressure may have an inconsiderable .efi'ect *on the total drop. It is also essentialthat the initial presi In order to so holdthese initial pressures, weighted gasometers have been employed,,since it is evident that pumps alone will not give sufficiently constant pressure. In'order that the, resistances may be considerable to effect a marked decrease in pressure'andyet be de- 0 'pendable,a long series of pipes of greater. than capillary diameter are employed. These pipes should be of'm'aterial not substantially corrodedfby any of theconstituents of the gas, brass having been'found satisfactory in practice. Resistances to the How of gases are often composed of constrictions or'orifices, in the -line. Such constructions .to accom; plish the large decrease inpressurehere; de+ sired would need to be of'aneXtre'me type, the orifice being merely a pin hole, or the constriction a capillary. As; such construca 7 tions are liableto change'in resistance owing to corrosion or sudden complete plugging by a comparativelysmall particle ofv solid ma terial, they are evidently not suited to the present purposes. V Referring then to Figure 1 theapparatus comprises a pair of air and hydrogen pumps shown at 1 and 2 both of which arebeltconnected to a driving motor 3. .Fromea'ch" pump the gas passes through acooling tank ,4 for condensing out moisture" and then 7 through a separator 5 in the air line and a V similarsepa'rator 6 in the hydrogen line,pre f- 3 5 erably of the baffle type, to remove suspended droplets of moisture. From there the gases pass through the bag filters 7 and 8 to remove particles of solid matter or oil which might be in. suspension, and through regulating 90 valves 9 and 10 to air -and hydrogen'gasony etersfll and112. From the gasometer [11 the air passes through a systemof' pipes 13fforming the resistance element and through'a'pipe 14:;t0 the combustion furnace n15, Thehydrogen passes from the gasometer12 through the resistance pipinglfi and" the'pipe 17 to, the furnace jT-he size and length of the resist ance piping are, of course, dependent on -'the I capacity of, the plant and the pressure drop desired-the smaller the volume of gasfrequired, the longer the piping of a given size, .or'the' smaller the piping of a given length forequalpressure drop; Preferably piping eifects might not be noticeable. 7

This furnaceis shown in. detail inFi -ures e V 2 and 3 and comprises a casing 18 lined with about 4 inch in diameterwould be about the smallest slzesuccessful in order that capillary an insulating medium such as magnesia and fire br1clc19'leav1ng' a longltudinal passage for combustion at the center. This space is preferably partly filledwith pieces of fire rick as 20 toincrease the refractory surface .The air and hydrogen are conveniently, sup v plied to this furnace through'concentrie pipes 21 and 22 passing through a flange 24 which may be boltedbya plurality of boltsi25 have ting pivotal connection with a flange 26 fast 20 drogen pipe 171 visconnected to the inner pipe to the end plate 27-of the, casing 18. The by 22, and the air pipeilt is connected to the v outer pipe 21. The inner end ofthe'se' pipes pipes 21and-22 are connected by flexible tubfurnace, a smallplug cock as. 30 and 31ibeing provided in-each'linelto adjust the'quantity' of gasinitially. On starting up after the. 'gasometers are full and hydrogen has run 21 a nd 22 terminates in a combustion nozzle 27 which extends within the combustion,

chamber when the flangesQ-it and 26 are bolted together. For conveniencein lighting, the

ing with the pipes 14 and 17 soth at'the combustion nozzle 27 may be withdrawn from the from the nozzle until tests. show it free of oxygen, the hy drogen plug lcock'is partly y' closed so that the gasmay be safelylighted,

and the nozzle is then inserted in thelfurnace, the flanges bolted, andboth plug cocks opened wide. This procedure eliminates the danger of an explosion in the furnace on starting the 1 apparatus- .arating out of thelwate'r may be carried out,

;in.stages,-as shownfinFigure 1, an air cooler 35 being first employe'd then awaterf cooler 36., aQbaffie separator 37 for removing "the. droplet-s of water,' and finally; if desired ir efrigerated: brine in duplicate coolers 38, one

i The hotmixture -of'initrogen and supers I heated water vapor in the furnace may theiibe cooled, and the water removed so that thenitrogen may be utilized. Thi's cooling and sep- 7 of these coolers being operated while thein:-

" .crustationsof ice are removed-from the other.

, thispoint.tl e gasfimay be tested andfupon excess 10f e ther oxygem or hydrogen being;

' fshown adjustmentsmay be made in the ap par atus. 'jltis foimdcpnvenient to make pre- I liminary rough ad ustments inthe resistances.

by varying: the length of pipi g through whichthev gases flow. 7; Fine,adjustmentsfare itheni determined" varying the Weight .ap plieol 'to the gasom'eter. bells, it' being desirabls t-0i .lnaintain' these weights, as nearly equal as; possible to'impart equal Init al pressures-in.

view of the fact that the final pressures of i the gases as they are mixed are equal. The

resistance elements are preferably composed of a series of pipesjoinedaat their ends by cross connections 40 which have removable access may be had by a cleaning rod in order that'the interiorsof the pipes may be periodi-j cally and readily cleaned.

Thepressure which may be successfully applied to gases by means of gasometers is limited by the available height of the gasometer, tank since this pressure is balanced by the head of the sealing liquid. Ithas been 'found in practice that pressure of two pounds.

is sufiicient in this apparatus the gasometer.

bells being immersed in non-aqueous liquid such asoil whichfnot only serves to prevent admission of moistureto the gas but also serve to lubricate the rollers carried by the gasometerbells-and which engagethe inner faces of thetanks. By thismeanstherollers are always kept in free runningcondition and failureof theigasomet'ers to freely func' l a t ion isreduced to theininimur'n. I It is desirable that. the pumps shall be able Qtopump the gas'at somewhat higher-pressure into these gasometers, fparticularly in view of the resistancesinterposedlin the shape of soforthh For this purpose the pumps maybe designed to operate at, say, four pounds per theapparatusfor removing'w'ater, dust, and Isis square ,inch, it being preferable to providev w safety va'lvesat the outlet side ofthese pumps in order to. prevent an excess pressure being 'ure 1 at and 46, the valve 45 for .thelair supplied; Such valves-areindicated on Fig- I line P bly exhaustinginto the atmos phereand the valve 46 forthe hydrogen line preferably exhausting through the pipe. 47- into the pump intake. This constructionpro= ,vides ample pressures of the gases whileij i suringagainst excessive pressures;

upper end of each gasorne teifbell terminates in a flange 50 within which is a space for the reception of sectoral: weights. 51 :(see Figure 4), by which the pressureexerted' onthe gas by these bells may be regulated. Centrally. -Iofthis fiangeiis pivoted to the upper end of the bell anarm 52 .to the upper end of which I islpiyoted aleve'r 53. :Both these levers are pivoted to a collar 5% fixed to. apost55jeXtendf-f ing. upwardly from fa .fr-ame 56 which supi].

ports the, gasometers. V g

. 0, plugs opposite the ends of; the pipes so that through which .wardly. If the gasometer bell rises sufii'-' ciently, the rear pivot 6'lfis engaged by the lowerend of the slot in the corresponding .68 terminating in a nearly horizontal position ofthe lever 66 this weaker Depending from thelevers 5'3 between their 7 ends are rods 156 having rack portions 57. To' the lower end of each bar is pivoted a pair of links 58 as shown in Figuresfi and 7 preferably having turnbuokles 59 intermediate thereof for adjusting theirl'engths. These links 58 terminate inslotted-lower extremities ried, at opposite ends of an'arm 62 fixed to a rock shaft 63 ing frame. 'As shown in Figure 7 the rear arm.58 is considerably shorterthan theforward arm so that in-the position shown the pivot 61 bears toward the lower end. of the rear arm and toward the upper end of the slot in the forward arm. By. this construction, if the gasometer bell lowers sufficiently, the forwardpivot 61 is engagedby' the upper end of the slot on the corresponding link, rocking the forward end of the 62 down arm' 58,-the rear end of-rock arm 62being V raised. It is therefore seen that by movement :of the gasometer bell either upwardly or. downwardly beyond'determined points the rock shaft 63 is rocked in the same direction. 'Pivoted above the switch 48 at 65 is a lever '66 having a slotted rear end 67 taking over one of the pivot pins 61. Forwardly of the pivot 65 this lever carries a depending arm hook 69; In the normal hook 69 extends beneath the switch-tripping finger 70 which is'depressed to substantially the position shown "in Figure 7 when the switch 48 controlling the motor" 3" is closed. It is therefore evident that when the rock shaft 63 is rocked by either too great an ascent or descent of either of the gasometer bells, the

outer end of the lever 66 is swung upwardly-and the hook 659 engagingbeneath the finger 70 moves the switch to the off position. Whenthe apparatusis first started, itis evident that thebe'lls are at their downward limit of motion, this causing the hook 69 to be in its raised position so asnormally to hold the switch open and prevent'the starting of the apparatus. 1' The arm 68 frna ybe.

swung outwardly from beneath the finger 70 by the operator andfthe fingermay then be thrown down and the apparatus started. As the gasometer bells rise lever: 66 may be depressedby actuation 0f li'andle 66@, the hook 69 riding over-theouter face'of thel finger and swinging'thereunderias the inner end of .the'lever strikes the stop pin'84c"whereupon the safety appliance automatically assumes ,its operative position]plNith this construc-v tion should either one of the pumps fail allowing its gasometerto fall, the motor-is stoppedwhen the gasometer bell has reached a predetermined position, while should either are passed pivots61 carournaled at 6d in thejsupportis in normal operating position. Fronrtliis trio arcs 77 and, 78, of'diiferent diameters joined by inclinations 79. Cooperatingwith this cam is a follower. comprising a yoke member 80 having thereon rolls 81 and 82 extending on diametricallyopposite sides ofthe; cam 76, The lower end of this yoke 80- is attached to the valve stem 83 of the regulat gear having fixed thereto a cam 7 6. "This cant 1 has its periphery formed as a pair of concening valve. 'The position of the cam 76 shown in'Figure 7 is the one it assumes when the gasometer bell at downward limit ofniotion. 'When the apparatus is put into oper-' ation, thebell rises and the cam 7 6 turns correspondingly until the rollers 81, 82 ride on the inclinations .79, at which t-ime the bell position any slight rise of the bell will move the-- cam face 77.nearerthe roller 82 and will thus force the valve sten1-83 downward; A lowering of the bell will move thefca n face 77 nearer the roller 81 and will thus force the valve stem 83 to rise- These partsare so designed that as; the gasometer bell lowers the valve is openedandas it risesjthe valve is closed, motion of 'thevalve taking place plitude of motion of the gasometer bell at entirely within a comparatively small am either limit of the desirable motion thereof;

Should either'ofthese valves 'fail ,to f'unc- 7 tionfand the corresponding bell travel either too highor too low the supply of gas thereto is stopped in ample time to avoid trouble by the action of the switch mechanismbefore described. f 1

"Ithasbeen found that with an apparatus. of this description supplies of gas mayfbe furnished to the furnace suliiciently accu-' rately'to require little attention and to perv e znstituentsorfinallgas.=

vWhile this'apparatus has been described in connection with the production of. nitrogen by the combustion of hydrogen mar, it is jevideiit-"that means for regulating the flow of a'plurality of'anygaseswhijch i-tfis w 1 necessary or desirable should takeplacein balanced ratio might employ features of this invention.

' 'An'embodi"jentfof this invention having thus been described itxsliould be evident that many changes andfniodifications inight'be made i therein 5. w tl i'o'ut" departing, from its f spirit :or scope asdefinedbytheappended" v Y claims,

1. 111 a a parent bf the "class-described, I

- 'atpressure regulator receiving gas from said pump and 'containing a. predetermined yol- 'aplurality of gas pumps, a common motor for actuating sald pumps, a gasometer for receiving the gas from each pump, 21I1l'111111-"' 'ually reset means actuated by. abnormal movement of any gasome'ter for stopping said motor. 7 v v '2. In an apparatus of the class descrlbed,

a pump, a inotor for actuating said pump',

a 'gasometer for receiv inggas from'said pump, and meansvforstopping said motor rection from norn'laloperating postion. ,7

3.111 an apparatus offthe class described, a gaspump, a motor for actuating said pump,

umegof gas under normal operating conditions, and means actuated by excessive variation from the normal volume-of'gasin either direction in said. pressure regulator for stopping. said motor. I r

4.- In an apparatus of the: classdescribfed,

7 upon ,m'ovement of thexb'ellj of said gasometer I beyond a predetermined distance in either (ll-V driving said pumps, a switch for controlling i i said motor, a gasometer' for receiving gas from each of said pumps, means-actuated when the bell of any of said gasometers either 'a rises, or falls to predeterminedpoints'jtor opening'said switch, and means whereby said: I switch-opening device may be held nopera-.

tive during the initialperiod of filling the gasometers.

10. In; an apparatus of the classdescribed, f a plurality of gas pumps, meansfor driving said, pumps, 9. pressure regulator to receiveeach gas,a valve between-each of said pumps and its pressure regulator, meansoperated by volume of said regulators for controlling said Valyes, and means'operatedby variation ot volume of any of said regulators beyond predetermined limits for. rendering inoperative said drivingmeans. 1

1 In testimony whereof I have affixed-my sig nature. r

a plurality of gas pumps, an 'electric motor a trolling said motor, agasometer for receiv- 7 ing gas fromjeach of said pumps, and manually reset 'means actuated by abnormal movement, of the bell of ahy 0t said gasometers: for opening said'switcli. V

5. In an apparatus o f'the class described,

for-actuating saidpumps, a switch for 0011f a plurality of'gas pumps, asingle electric motor for. actuating all said pumps, a switch for controlling said motor, .a gasometer for assreceiying gas from each of said pumps, and

. meansactuated when the bell of any of said "'gasomete'rs either rises or falls to predetermine'd points for opening said switch.

7 6. 'An'apparatus oftlie class described comprising a pump, an electric, motor for drivfrom said pump, a starting switch for said motor mounted'adjacent said gasometer,- a rock shaft, a two-armed lever fixed to said shaft lostmotion connections from the bell of said gasometer to opposite endsof said lever, whereby raisingor lowering of said A gasometer bell; beyond determined points P-rocks said' shaft inone direction, and a. concontrol switchwhen said shaft is rocked by either ef smd lost'motion CO'lQilQQiZlOIlS.

--driving means onabno bell in either direction.

ing saidpump, a gasometer'for receiving gas uection from {said shaft actin to'tri said' .t: e P

V 7. Iii'Pan'appa -atus ofthe classjdescribed, o pumpgti gasometer, a valve interposfedfbetween said pump and gasometeniand means Q 7. a'ctuated-iby'themovement of the bell of said I ,"gasometer forcontrolling said valve. 1 j

8 In, anlappa'r'atussof. theclass described,

apu-mp, means for driying said'pumga gas ometer,"and.'connections trom'thebe'llofsaid V gasometer for rendering] inoperative said rnial moyementofsaid In apparatus of the? class describedja; I plurality of gaspumps,;an-electric motor for WALLACE B. VAN, A'RsDEL; V V 

